| University of Maryland Extension instructor
052721_cicadas_at_Antietam_National_Cemetery_2
Spawn of cicadas X has arrived in southern Washington County. Here they stand in the shadow of the Antietam National Cemetery on May 27, 2021.
Julie E. Greene, The Herald-Mail
BOONSBORO – ladybug. Lacewing. Ground beetles. Wasps.
What do all these insects have in common? They are the good guys, the beneficial insects that help keep bad bugs at bay in our gardens.
Nine out of ten insects are useful. Yes, most of those flying, crawling, buzzing, and burrowing bugs out there are actually helping you fight the few bad bugs that harm plants.
How? Some are predators that eat nasty bugs. Others are parasites that lay eggs on nasty bugs to feed their babies.
So instead of reaching for the spray bottle when a beetle strolls over your petunias, pause. Does it harm the plant? Or is a good guy just walking around?
Think before you crush or spray. When you take out good bugs, you take out your allies.
Instead, send me a photo or bring me a sample so I can identify the insect and suggest controls if necessary. Let’s work together to maintain and build your army of helpful insects.
Knowing useful insects is loving them. So let’s meet a few.
The ladybug is a good figurehead for beetles. It happily eats thousands of aphids in its lifetime as well as scales, spider mites, whiteflies and more.
Lacewing are beautiful insects with pointed wings (hence the name). They may look delicate but are voracious hunters who will eat a variety of insidious beetles.
Some wasps are parasitic and lay their eggs on harmful insects. There is even one called a scoliid wasp that lays its eggs on Japanese beetle maggots in the ground.
Other generalist predators like praying mantis and killer bugs stalk and eat a variety of insects – good and bad – to keep their populations balanced.
I bet now that you’ve learned about a few useful insects, you’d like to know how to lure more into your yard. Here are a few tips.
First, give them the basics: food, water, and shelter.
Many insects need pollen and nectar. So make sure something is in bloom from spring to frost for both food and shelter. Native plants do best to support native insects.
Many beneficial insects are small and risk life and limb if they drink water from a traditional bird bath. So put water in shallow containers. A saucepan saucer will do the trick.
Some plants attract beneficial insects better than others. Herbs with their tiny flowers are just right for small beneficial insects.
Daisy-shaped flowers such as coneflower and zinnia are magnets for good beetles, as are plants with umbrella-shaped inflorescences such as yarrow and dill.
One of the best things you can do for beneficial insects is to stop or limit the use of chemical insecticides. Chemicals do not discriminate and kill both good and bad bugs.
This doesn’t mean you can’t control garden pests. I’m just suggesting a gentler approach.
Insecticidal soap, horticultural oil, and Bt – the holy trinity of biological controls – fight most nasty insects. Add in cultural practices like hand picking, row covering, and crop rotation and you have an arsenal of crackerjack controls.
Don’t let bugs annoy you. Most of them are friends. Hug her. Encourage them. And deal quickly with the few nasty errors with organic controls. They work.
Annette Cormany is the Horticultural Extension Educator and Master’s Gardener program in Washington County for the University of Maryland. She can be reached at 301-791-1604 or acormany@umd.edu.
